/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.pig.pigpen.editor.textEditor.errorHandler;

import java.util.Iterator;

import org.eclipse.core.resources.IMarker;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.source.IAnnotationHover;
import org.eclipse.jface.text.source.IAnnotationModel;
import org.eclipse.jface.text.source.ISourceViewer;
import org.eclipse.ui.texteditor.MarkerAnnotation;

public class ErrorAnnotation implements IAnnotationHover {

    public String getHoverInfo(ISourceViewer sourceViewer, int lineNumber) {
        // TODO Auto-generated method stub
        return getMessageForLine(sourceViewer, lineNumber);
    }

    private String getMessageForLine(ISourceViewer viewer, int line) {
        IDocument document = viewer.getDocument();
        IAnnotationModel model = viewer.getAnnotationModel();

        if (model == null)
            return null;

        String message = null;

        for (Iterator it = model.getAnnotationIterator(); it.hasNext();) {
            Object obj = it.next();
            if (obj instanceof MarkerAnnotation) {
                MarkerAnnotation annotation = (MarkerAnnotation) obj;

                if (compareLine(model.getPosition(annotation), document, line)) {
                    message = annotation.getMarker().getAttribute(
                            IMarker.MESSAGE, null);
                }
            }
        }
        return message;

    }

    private boolean compareLine(Position position, IDocument document, int line) {
        if (position.getOffset() > -1 && position.getLength() > -1) {
            try {
                return document.getLineOfOffset(position.getOffset()) == line;
            } catch (BadLocationException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        return false;
    }

}
